AliasVault: Server-Side Request Forgery via DNS rebinding in Favicon Extraction

AliasVault is a privacy-first password manager with built-in email aliasing. Prior to 0.30.3, the AliasVault server API favicon extractor validates a user-supplied hostname with a first DNS lookup but allows the HTTP client to perform a second DNS lookup when connecting. An authenticated low-privileged user operating an attacker-controlled authoritative DNS server can return a public address during validation and a private address during connection, causing a publicly reachable self-hosted server to issue HTTP or HTTPS requests to internal hosts. A valid image response is returned in Base64 form, while other responses can expose limited timing and error information for internal-network reconnaissance. Exploitation requires a publicly reachable self-hosted instance with public registration enabled, an authenticated AliasVault account, an attacker-controlled authoritative DNS server, and a resolver that permits rebinding; default checks limit requests to ports 80 and 443. The browser extensions, web application, and mobile applications are not affected. This issue is fixed in version 0.30.3.